Selenium Contamination in Water
Selenium Contamination in Water

Author: Pooja Devi

Publisher: John Wiley & Sons

Published: 2021-05-12

Total Pages: 436

ISBN-13: 1119693543

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The contamination of environment and water resources by Selenium (Se) and its oxyanions from various sources are emerging contaminants of significant health and environmental concern. The primary sources include agricultural drainage water, mine drainage, residues from fossil fuels, thermoelectric power plants, oil refineries, and metal ores. Various methods and technologies have been developed which focus on the treatment of selenium-containing waters and wastewater. High concentrations of selenium in water cause various adverse impact to human health, such as carcinogenic, genotoxic, and cytotoxic effects. But in the lower concentrations, it is a useful constituent of the biological system. The range between toxicity and deficiency of selenium is minimal (40 to 400 μg per day), due to its dual nature. Selenium Contamination in Water contains the latest status and information on selenium’s origin, its chemistry and its toxicity to humans. The book represents a comprehensive and advanced reference book for students, researchers, practitioners, and policymakers in working in the field of metalloids, in particular selenium. A special emphasis is given on its geological distribution, monitoring techniques, and remedial technologies. As such, the authors critically analyze the various techniques used for the monitoring and removal of selenium from water. Featuring chapters arranged according to the major themes of the latest research, with specific case-studies from industrial experiences of selenium detection and removal, Selenium Contamination in Water will be particularly valued by researchers, practitioners, and policymakers in working in the field of metalloids including selenium.

Toxicity Reduction
Toxicity Reduction

Author: Davis Ford

Publisher: CRC Press

Published: 1998-05-18

Total Pages: 376

ISBN-13: 9781566766340

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In the reauthorization of the Clean Water Act in 1987, the U.S. EPA specifically addressed toxics management. In addition to the requirement to eliminate discharge of toxics, there can be a requirement to conduct a toxicity reduction evaluation (TRE). The scope of toxicity reduction varies from the very simple and inexpensive to the highly complex and costly. This book, volume three of the Water Quality Management Library, provides a complete overview of toxicity reduction evaluation. The book presents the testing and removal of toxicants, toxicity testing procedures, sampling techniques, baseline collection data, and source identification. Plus, the book presents toxicity reduction methodologies including unit processes necessary for organic toxicant control using biological and physical chemical methodologies as well as selected unit processes necessary for inorganic toxicant control.

Anaerobic Treatment of Mine Wastewater for the Removal of Selenate and its Co-Contaminants
Anaerobic Treatment of Mine Wastewater for the Removal of Selenate and its Co-Contaminants

Author: Lea Chua Tan

Publisher: CRC Press

Published: 2018-09-03

Total Pages: 20

ISBN-13: 0429828411

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Selenium (Se) pollution has led to several cases of severe aquatic ecosystem deterioration due to Se poisoning caused by bioaccumulation over time. However, the removal of selenate (SeO42-) from wastewater streams with co-contaminants has been largely considered as a black box in anaerobic biological systems using mixed consortia. This research aimed at addressing the effect of wastewater characteristics, i.e. co-contaminants such as nitrate (NO3-) and sulfate (SO42-), heavy metals and pH, on the biological reduction of SeO42- and evaluating process integration for Se-laden wastewater treatment with co-contaminants. This study demonstrated that the presence of co-contaminants can actually be beneficial for Se removal provided that the concentrations are carefully monitored and appropriate operating conditions and process configurations are used. The Se removal (total Se and SeO42-) efficiency increased by ~30% in the presence of NO3- and/or SO42- compared to systems with SeO42- alone. Additionally, an integrated process of an ion exchange (IX) column and bioreactors showed improved overall removal capacity for SO42- and total Se. The knowledge and information gained from this research can help in the advancement and application of biological processes, i.e. predicting of reactor performance, solving specific design or practical problems and implementing novel treatment techniques for Se-laden mine wastewater.